The present disclosure relates to methods and systems of monitoring and regulating a xerographic marking device by use of performance monitoring to adjust tone reproduction curve (TRC) cycle-up criteria.
TRC cycle-up criteria is an extremely important set point in the determination of a xerographic marking device's performance in terms of cycle-up convergence (CUC) time and image quality regulation. System properties can drift over time in a print engine, negatively impacting system performance and print quality stability. In order to maintain stable performance, a xerographic marking device uses process control schemes by employing optical density sensors, for example, an extended toner area coverage sensor (ETAC), as well as other types of sensors (color engines may have multiple toner control sensors and optical density sensors). Utilizing sensors to measure the state of development allows for a determination on whether or not the TRC mean is within desired TRC cycle-up criteria. If a sensor identifies that the TRC mean is within the TRC cycle-up criteria, the system will allow for printing of a print job to commence. However, if the sensor indicates that the TRC mean falls outside of the TRC cycle-up criteria, indicating that properties have shifted and therefore the quality of the print may be affected, printing will not commence until the system is brought within the criteria's specifications.
Noise level estimates can van, dramatically depending upon machine conditions. Therefore, due to the noise level estimates caused by a sensor and/or the system itself, a read from a sensor may not reflect the true state. For example, the sensor may indicate that the TRC mean falls outside the TRC cycle-up criteria when in fact the TRC mean is on target. Thus, TRC cycle-up criteria that are too tight relative to noise level estimates may unnecessarily delay the start of a print job. This is not only a customer annoyance, but it also has a direct impact on component and material life, that is, parts usage and degradation, while not productively printing. Similarly, TRC cycle-up criteria that are too loose relative to noise level estimates may prematurely initiate a print job prior to the point in time when the TRC is reasonably close to target. This not only impacts system performance, but print quality/stability as well.
Currently, TRC cycle-up criteria are static and therefore problematic. As mentioned above, TRC cycle-up criteria that are too tight or too loose relative to noise level estimates may have a negative effect on system performance, print quality/stability, improperly delaying a print job and/or prematurely initiating a print job. Such static cycle-up criteria with respect to noise levels hinder the critical task of print proofing, color calibration, and the like.